Lichen planus (LP) is a chronic, immune-mediated dermatosis, clinically characterized by the classic “5 P’s”: pruritic, purplish, polygonal, planar papules, and plaques. While typically LP is idiopathic, the Koebner phenomenon may trigger LP by trauma, infections, medications, or foreign substances such as, in this case, tattoo pigments. A 27-year-old Filipino male presented with a 10-month history of intensely pruritic papules and plaques involving both tattooed and adjacent nontattooed regions of the forearms. Lesions initially appeared as papules along the tattoo margins approximately 1 year after tattoo placement and subsequently, spreading to form confluent plaques. Despite multiple courses of high-potency topical corticosteroids, symptoms persisted with progressive lesion thickening. Dermoscopy was performed, but the findings did not conclusively indicate LP; therefore, a biopsy was done to confirm LP. Owing to the extent of involvement and lack of steroid response, the therapy was transitioned to tacrolimus 0.1% ointment applied twice daily. The patient experienced a marked reduction in pruritus, flattening of papules, residual postinflammatory erythema, and no reported adverse effects within 2 weeks. This case highlights the therapeutic potential of topical calcineurin inhibitors in managing LP, particularly in cases where there is resistance to corticosteroids. Tacrolimus 0.1% ointment may present a safe and effective alternative for disseminated or steroid-refractory LP, warranting consideration in clinical practice.

Human ; Male ; Adult: 25-44 Yrs Old ; Adrenal Cortex Hormones ; Inflammation ; Lichen Planus ; Tacrolimus ; Treatment ; Tattoo